Mechanical level sensors such as spirit levels are well known and can be adapted for use in determining the tilt of exercise equipment. For example, a spirit level can be attached to the center of a fitness or weightlifting bar. While appropriate for certain types of exercise such as when performing a bench press, where the spirit level is visible to the user throughout the exercise routine, in other exercise the fitness or weightlifting bar is not always or never visible. For example, some exercises involve the user lifting a barbell over head or placing a barbell on the shoulders. In such circumstances a spirit level is inappropriate because it is not visible to the user during all or part of the exercise routine and therefore cannot provide instantaneous feedback about the tilt of the exercise equipment.
Oftentimes people who are weightlifting will have uneven muscle mass, which can result in lifting weights unevenly. As a result, working out in this way over time will potentially harm and damage joints, muscles, and/or bones. Exercising in an unbalanced form can ultimately lead to physical injuries or compromise the benefits of exercising.
People have a tendency to preform repetitious motion in an unbalanced form while weightlifting. It is known that the perception of balance can differ among people. For example, something that seems level to one person may appear tilted to another person. Also, when doing repetitive activities such as weightlifting distractions such as other people, objects, noises, and/or fatigue can affect performance and perception. Sports and recreational activities that need to have proper alignment and limited mobility should be performed correctly to prevent physical injury and to maximize the benefits. Motions that are exerted during physical activities that should be performed at a leveled (even, steady, repetitious consistent) form can cause physical injury if not done properly. In physical proper form can minimize the potential for further injury and can maximize the benefits of the therapy.
Exercises using weights are often used in training and in physical therapy. Weightlifting equipment can include barbells in which removable weights can be attached on opposite sides of an elongated rod. Various exercises can be performed using the barbell. While performing an exercise, the barbell may tilt with respect to vertical thereby exerting more force on one side of a user's body. Barbell exercises are more safely and effectively performed when the barbell remains level throughout the exercise regimen and during each repetition of the particular exercise. For example, when bench pressing weights, it is desirable that the bar remain level as the bar is pushed away from and then toward a user's chest in a continuous motion during a repetition. By knowing the degree of tilt during the exercise a user can adjust the tilt during the repetition.
Some exercises may require faster motion than others and/or some users may perform an exercise at a faster rate. Instantaneous tilt monitoring allows a user to adjust alignment during each repetition of an exercise routine and thereby perform each repetition in a safe and efficient manner.
Apparatus for monitoring the levelness of exercise equipment are disclosed in U.S. Pat. No. 4,888,875 to Strother. The apparatus disclosed by Strother include a spirit level in which a bubble or ball moves within a fluid to indicate the degree of levelness. These levels can be difficult to read and to control in a dynamic environment such as when using exercise equipment and are better suited to static environments such as in construction. For example, when using a weightlifting bar the degree of levelness can change rapidly as the bar tilts to the left or to the right during a single repetition. The motion of a bubble or ball within a fluid can either be too rapid or too slow to effectively capture the degree of levelness and accurately communicate the levelness to the user in a meaningful way to facilitate the user's ability to adjust the levelness during an exercise repetition. Spirit levels are impractical for use in a dynamic environment where the title angle can change rapidly and a user requires immediate feedback to bring the equipment level. Another disadvantage of spirit levels is that they are basically binary devices, meaning that when the spirit level is titled the bubble or ball will move to the extreme right or to the extreme left of the fluid tube at a rate determined by the degree of tilt, and will be centered in the fluid tube when the apparatus is level. In a dynamic environment, it is useful to have an immediate measurement and readout of the degree of tilt, not simply whether the apparatus is level or not level. By knowing the degree or extent of tilt, a user is more able to actively adjust to maintain the levelness of an apparatus. A small degree of tilt requires a small exertion of effort to correct the tilt and bring the exercise equipment to level, while a large degree of tilt requires a large exertion of effort to correct the tilt and bring the exercise equipment to level.
Apparatus for dynamically monitoring the level of exercise equipment such as a weightlifting bar and informing the user of the degree of levelness are desired.